Benzothiazole derivatives for plant growth and development modification

ABSTRACT

Benzothiazole compounds of the following structural formula modify the growth and development of plants: ##STR1## wherein U is selected from -hydrogen, -halogen, -lower alkyl, -lower haloalkyl, -lower alkoxy, -phenyl, and -phenoxy optionally carrying -halogen and -lower haloalkyl substituents; 
     V is selected from -hydrogen and -halogen, or U and V taken together are --C 4  H 4  -- joining adjacent ring positions; 
     Y is selected from -hydrogen and -lower alkoxy; 
     Z is cyclic and either (a) -phenyl optionally carrying 1 or 2 substituents independently selected from -halogen, -nitro, or two substituents taken together are --C 4  H 4  -- joining adjacent ring positions, or (b) Z may be a saturated or partially unsaturated carbocycle, optionally carrying a bicyclic --CH 2  -- bridge, or an aromatic heterocycle containing 1 or 2 nitrogen atoms; and 
     Z includes a 2-oxycarbonyl substituent of the formula 
     
         --COOW 
    
     in which W is selected from -hydrogen, -lower alkyl optionally substituted with -alkoxycarbonyl, and an agriculturally acceptable cation.

This invention is in the field of organic chemical compounds; morespecifically, it pertains to novel 2-(oxycarbonylcyclic)benzothiazoles,processes and intermediates thereto, plant growth and developmentmodifying compositions containing 2-(oxycarbonylcyclic)benzothiazoles,and to the use of 2-(oxycarbonylcyclic)benzothiazoles for modifying thegrowth and development of plants.

A number of organic chemical compounds modify the growth and developmentof plants. Application of an organic chemical to plants may cause deathof the plants. Such chemicals are referred to as herbicides. Althoughbroad spectrum herbicides have recognized utility, herbicidal activityis often more desirable if it is selective, sparing crops, but killingweeds. Occasionally organic compounds are discovered which are notsimply nutrients, but, when applied in the recommended manner,selectively modify the normal growth and development of plants and donot kill them.

Beneficial effects from such modification include increasing the yieldof fruit, seeds, fiber, or other plant products. Another beneficialeffect may be an increase in the nutritional value of food productsderived from the plants. It is a beneficial effect of some compounds tofacilitate harvesting the plant product. Yet another beneficial effectin certain cases is an increase in the products's storage life. Suchchemical compounds, beneficial to plants in small amounts, are referredto as plant growth regulators. Plant growth and developmentmodifications leading to such effects include, but are not limited to:root initiation; set, development, ripening and abscission of fruits;plant size and shape; suppression of lodging; control of axillary budsand lateral shoots; metabolism regulation, including senescence;breaking or enforcing dormancy in seeds, buds, and storage organs;promotion or delay of flowering; defoliation; desiccation; and growthpromotion under stress.

Sometimes an organic chemical compound displays plant growth anddevelopment regulation characterized by both herbicidal activity andplant growth regulator activity depending upon the species of plant, thetime of application in the plant growth cycle, the site of application,and the amount of chemical employed, i.e., the application rate.

The plant growth and development modifying2-(oxycarbonylcyclic)benzothiazoles of this invention are in the lattercategory. In general, they can be made to behave as either herbicides orplant growth regulators depending upon the way they are used.

An example of a 2-(oxycarbonylcyclic)benzothiazole is2-(2-carboxyphenyl)benzothiazole, which is a condensed ringheteroaromatic compound of the following structural formula: ##STR2##The ring atom numbering scheme is shown for convenient reference. Other2-(oxycarbonylcarbocyclic)benzothiazoles are numbered in a similarfashion, but in 2-(oxycarbonylheterocyclic)benzothiazoles numbering inthe heterocyclic ring conventionally begins with a hetero atom. For thesake of clarity herein, however, the atoms of an oxycarbonylheterocyclicring in such compounds are numbered beginning with the atom bonded tothe benzothiazole moiety, as in the formula which appears above, andthis is reflected in the names given the2-(oxycarbonylcyclic)benzothiazoles of this invention.

Many of the 2-(oxycarbonylcyclic)benzothiazoles within the scope of thisinvention appear to be new compounds, but others of them have beendisclosed. 2-(2-Carboxyphenyl)benzothiazole and the corresponding methylester are known; see Chem. Abstr., 51, 373c (1957). In addition,2-(2-carboxyphenyl)benzothiazoles carrying certain substituents in thecarboxylated ring have been described; Ukranian J. Chem., 32, 706(1966). The latter reference also discloses2-(carboxypyridinyl)benzothiazole derivatives.

GB 1,090,497 discloses the herbicidal activity of certain substituted2-phenylbenzothiazoles. U.S. Pat. No. 4,319,026 describes 2-substitutedbenzothiazole plant growth regulators.

According to the present invention 2-(2-oxycarbonylcyclic)benzothiazolesof the following formula have been found to modify the growth anddevelopment of plants: ##STR3## wherein

U is selected from -hydrogen, -halogen, -lower alkyl, -lower haloalkyl,-lower alkoxy, -phenyl, and -phenoxy optionally carrying -halogen and-lower haloalkyl substituents;

V is selected from -hydrogen and -halogen, or U and V taken together are--C₄ H₄ -- joining adjacent ring positions;

Y is selected from -hydrogen and -lower alkoxy;

Z is cyclic and either (a) -phenyl optionally carrying 1 or 2substituents independently selected from -halogen, -nitro, or twosubstituents taken together are --C₄ H₄ -- joining adjacent ringpositions, or (b) Z may be a saturated or partially unsaturatedcarbocycle, optionally carrying a bicyclic --CH₂ -- bridge, or anaromatic heterocycle containing 1 or 2 nitrogen atoms; and

Z includes a 2-oxycarbonyl substituent of the formula

    --COOW

in which W is selected from -hydrogen, -lower alkyl optionallysubstituted with -alkoxycarbonyl, and an agriculturally acceptablecation.

In the aforesaid description and wherever employed in this applicationthe terms "halogen" or "halo" mean fluorine, chlorine and bromine.Similarly, the term "lower alkyl" means a straight or branched chaincontaining 1 to 6, preferably 1 to 4, carbon atoms, and the term "loweralkoxy" contemplates bonded to oxygen a straight or branched chaincontaining 1 to 6, preferably 1 to 4, carbon atoms. The term "haloalkyl"or the like means one or more hydrogen atoms has been replaced byhalogen. "Agriculturally acceptable cation" includes, but is not limitedto, alkali and alkaline earth metals such as sodium, potassium, calcium,lithium, and magnesium, or other metals such as copper, zinc, aluminumor iron; ammonium, mono-, di-, or tri-substituted ammonium, such asmethylammonium, 1-methylethylammonium, diethylammonium,triethylammonium, hexylammonium, dodecylammonium, ethanolammonium,diethanolammonium, hexanolammonium, or dodecanolammonium.

In addition to the new 2-(2-oxycarbonylcyclic)benzothiazoles as oneaspect, the instant invention also includes plant growth and developmentmodifying compositions comprising in admixture with an agriculturallyacceptable carrier a plant growth and development modifying effectiveamount of at least one of the aforesaid2-(2-oxycarbonylcyclic)benzothiazoles. Furthermore, the inventionincludes as another aspect the method of modifying the growth anddevelopment of plants which comprises applying to the locus where suchmodification is desired a plant growth and development modifyingeffective amount of at least one 2-(2-oxycarbonylcyclic)benzothiazolewithin the aforesaid description.

Among the aforesaid 2-(2-oxycarbonylcyclic)benzothiazoles the mostattractive compounds, from the standpoint of plant growth anddevelopment modification, are those wherein U is a 5- or 6- substituentselected from -halogen, -lower haloalkyl, -phenyl, and -phenoxyoptionally carrying -halogen and -lower haloalkyl substituents. Withinthis set of compounds it is preferred that V and Y are -hydrogen andthat Z is selected from either -phenyl optionally carrying -nitro, or apyridine ring. As to W, the most active compounds are generally thosewherein W is selected from -hydrogen and an agriculturally acceptablecation.

If a 2-(2-oxycarbonylcyclic)benzothiazole is to be used as a herbicide,the most interesting compounds are2-(2-carboxyphenyl)-5-phenylbenzothiazole,2-(2-carboxy-3-nitrophenyl)-5-chlorobenzothiazole,2-(2-carboxyphenyl)-6-(2-chloro-4-trifluoromethylphenoxy)benzothiazole,and2-(2-carboxyphenyl)-5-(2-chloro-4-trifluoromethylphenoxy)benzothiazole.Preferred for both preemergence and postemergence application as aherbicide is2-(2-carboxyphenyl)-6-(2-chloro-4-trifluoromethylphenoxy)benzothiazole.

As plant growth regulators the most attractive properties are displayedby 2-(2-carboxyphenyl)-5-phenylbenzothiazole,2-(2-carboxyphenyl)-5-trifluoromethylbenzothiazole,2-(2-carboxyphenyl)-6-phenylbenzothiazole, agriculturally acceptablecation salts of 2-(2-carboxyphenyl)-5-trifluoromethylbenzothiazole,2-(2-carboxyphenyl)-6-(2-chloro-4-trifluoromethylphenoxy)benzothiazole,2-(2-carboxyphenyl)-6-phenoxybenzothiazole,2-(2-carboxy-4-chlorophenyl)-6-phenylbenzothiazole,2-(2-carboxy-5-chlorophenyl)-6-phenylbenzothiazole,2-(2-carboxy-4-chlorophenyl)-6-phenoxybenzothiazole,2-(2-carboxy-5-chlorophenyl)-6-phenoxybenzothiazole,2-(2-carboxyphenyl)-5-phenoxybenzothiazole,2-(2-carboxy-6-pyridinyl)-5-phenylbenzothiazole, and2-(2-carboxyphenyl)-5-(2-chloro-4-trifluoromethylphenoxy)benzothiazole.Among the latter compounds, 2-(2-carboxyphenyl)-5-phenylbenzothiazole,2-(2-carboxyphenyl)-5-phenoxybenzothiazole, and2-(2-carboxy-6-pyridinyl)-5-phenylbenzothiazole, especially2-(2-carboxyphenyl)-5-phenylbenzothiazole, are especially interesting.

The 2-(2-oxycarbonylcyclic)benzothiazoles of this invention can beprepared by adaptations of synthesis techniques described in theliterature. The following general technique is employed: ##STR4## Thestarting zinc salt can be prepared by the method of Allen and Mackay,Org. Synth., Coll. Vol. II, p.580 (1943). Alternatively, theappropriately substituted o-aminothiophenol can be used. The otherreactant is an appropriately substituted phthalic anhydride orcarbocyclic or heterocyclic anhydride. These processes will be clarifiedupon reference to the following Example.

EXAMPLE 1 2-(2-Carboxyphenyl)-5-phenylbenzothiazole

A stirred solution of 0.9 gram (0.006 mole) phthalic anhydride and 1.4grams (0.003 mole) zinc 2-amino-4-phenylsulfide in 25 mL of acetic acidwas heated under reflux for three hours. The reaction mixture was thenpoured into ice-water and the resultant precipitate collected byfiltration. The solid was dried and recrystallized from ethanol. Theimpure crystalline product was taken up in ethanol and concentratedunder reduced pressure to a residual solid. The solid was stirred withaqueous 2N sodium hydroxide and collected by filtration, washed withdiethyl ether, then dissolved in 300 mL of water. The resultant solutionwas combined with the 2N aqueous sodium hydroxide filtrate from above.The combination was filtered, and the filtrate was acidified withconcentrated hydrochloric acid. A colorless solid precipitate wascollected by filtration. The solid was recrystallized from a mixture ofethanol and water to give 0.6 g2-(2-carboxyphenyl)-5-phenylbenzothiazole; m.p. 177°-178° C.

The nmr spectrum was consistent with the proposed structure.

Analysis: Calc'd for C₂₀ H₁₃ NO₂ S: C 72.48; H 3.95; N.4.23; Found: C72.72; H 3.77; N 4.20.

Following is a list of other 2-(2-oxycarbonylcyclic)benzothiazoleswithin the scope of this invention prepared by similar techniques,together with mp (°C.) where applicable.

EXAMPLE

2: 2-(2-Carboxyphenyl)benzothiazole, mp 186-188.

3: 2-(2-Carboxyphenyl)-5-chlorobenzothiazole, mp 245-250.

4: 2-(2-Carboxyphenyl)-6-chlorobenzothiazole, mp 165-167.

5: 2-(2-Carboxyphenyl)-4,5-dichlorobenzothiozole, mp 242-245.

6: 2-(2-Carboxyphenyl)-4-fluoro-6-chlorobenzothiazole, mp 145-149.

7: 2-(2-Carboxyphenyl)-5-trifluoromethylbenzothiazole, mp 153-155.

8: 2-(2-Carboxyphenyl)-5-methylbenzothiazole, mp 218-220.

9: 2-(2-Carboxyphenyl)-6-methoxybenzothiazole, mp 208-210.

10: 2-(2-Carboxyphenyl)-6-phenylbenzothiazole, mp 181-183.

11: 2-(2-Carboxyphenyl)-naphtho[1,2-d]thiazole, mp 169-170.

12: 2-(2-Carboxy-5-chlorophenyl)benzothiazole, mp 120-125.

13: 2-(2-Carboxy-6-chlorophenyl)benzothiazole monohydrate, mp 149-150.

14: 2-(2-Carboxy-4,5-dichlorophenyl)benzothiazole, mp 125-127.

15: 2-(2-Carboxy-3-nitrophenyl)benzothiazole, mp 230-231.

16: 2-(2-Carboxy-4-nitrophenyl)benzothiazole, mp 234-235.

17: 3-(2-Benzothiazolyl)-2-naphthoic acid, mp 232-233.

18: 2-(2-Carboxy-4-chlorophenyl)-5-chlorobenzothiazole, mp 212-217.

19: 2-(2-Carboxy-6-chlorophenyl)-5-chlorobenzothiazole, monohydrate, mp223-226, dec.

20: 2-(2-Carboxy-4,5-dichlorophenyl)-5-chlorobenzothiazole, monohydrate,mp 264-267, dec.

21: 2-(2-Carboxy-3-nitrophenyl)-5-chlorobenzothiazole, mp 232.

22: 2-(2-Carboxy-4-nitrophenyl)-5-chlorobenzothiazole, mp 245-246.

23: 3-[2-(5-Chlorobenzothiazolyl)]-2-naphthoic acid, mp 242-243.

24: 2-(2-Carboxyphenylmethyl)-5-chlorobenzothiazole, mp 213-215.

25: 2-(cis-2-Carboxycyclohexyl)benzothiazole, mp 143-144.

2-(2-Carboxy-1-cyclohexyl)benzothiazole, monohydrate, mp 115-116.

27: 2-(cis-2-Carboxy-4-cyclohexyl)benzothiazole, mp 139-140.

28: cis-endo-2-Carboxy-3-benzothiazolylbicyclo[2.2.1]hept-5-ene, mp175-178.

29: 2-(2-Carboxy-4-pyridinyl)benzothiazole, mp 187-191.

30: 2-(2-Carboxy-6-pyridinyl)benzothiazole, mp 213-215.

31: 2-(2-Carboxy-3-pyrazinyl)benzothiazole, mp 158-160.

32: 2-(cis-2-Carboxycyclohexyl)-5-chlorobenzothiazole, mp 174.

33: 2-(2-Carboxy-4-cyclohexenyl)-5-chlorobenzothiazole, mp 185.

34:cis-endo-2-Carboxy-3-(5-chlorobenzothiazolyl)bicyclo[2.2.1]hept-5-ene,mp 162-165.

35: 2-(2-Carboxy-4-pyridinyl)-5-chlorobenzothiazole, mp 221-225.

36: 2-(2-Carboxy-6-pyridinyl)-5-chlorobenzothiazole, mp 257-260.

37: 2-(2-Carbomethoxyphenyl)benzothiazole, mp 71-72.5.

38: 2-(2-Carbomethoxyphenyl)-5-chlorobenzothiazole, mp 87-90.

39: 2-(2-Carbomethoxy-6-pyridinyl)benzothiazole, mp 112-113.

40: 2-(2-Carboxyphenyl)benzothiazole, 1-methylethylamine salt, mp110-125.

41: 2-(2-Carboxyphenyl)-5-trifluoromethylbenzothiazole,1-methylethylamine salt, mp 185-187.

42: 2-(2-Carboxyphenyl)-5-methylbenzothiazole, 1-methylethylamine salt,mp 148-150.

43: 2-(2-Carboxy-4,5-dichlorophenyl)benzothiazole, 1-methylethylaminesalt, mp 195-197.

44: 2-(2-Carboxy-3-nitrophenyl)benzothiazole, 1-methylethylamine salt,mp 202-204.

45: 2-(2-Carboxy-4-nitrophenyl)benzothiazole, 1-methylethylamine salt,mp 164-165.

46: 3-(2-Benzothiazoyl)-2-naphthoic acid, 1-methylethylamine salt, mp173-175.

47: 2-(2-Carboxy-4-chlorophenyl)-5-chlorobenzothiazole,1-methylethylamine salt.

48:2-(2-Carboxyphenyl)-6-(2-chloro-4-trifluoromethylphenoxy)benzothiazole,mp 178-180.

49: 2-(2-Carboxyphenyl)-6-chloro-4-phenylbenzothiazole, mp 199-201.

50: 2-(2-Carboxyphenyl)-6-phenoxybenzothiazole, mp 160-161.

51: 2-(2-Carboxy-6-pyridinyl)-6-phenylbenzothiazole, mp 210-212.

52: 2-(2-Carboxy-4-chlorophenyl)-6-phenylbenzothiazole.

53: 2-(2-Carboxy-4-chlorophenyl)-6-phenoxybenzothiazole.

54: 2-(2-Carboxyphenyl)-4,6-dichloro-7-(1-methylethoxy)benzothiazole, mp210-211.

55: 2-(2-Carboxy-4,5-dichlorophenyl)-6-phenylbenzothiazole, mp 248-249.

56: 2-(2-Carboxy-4-chlorophenyl)-5-phenylbenzothiazole.

57: 2-(2-Carboxyphenyl)-5-phenoxybenzothiazole, mp 154-157.

58: 2-(2-Carboxy-6-pyridinyl)-5-phenylbenzothiazole, mp 194-196.

59: 2-(2-Carboxyphenyl)-4,6-dichloro-7-(1-methylethoxy)benzothiazole,1-methylethylamine salt, mp 150-152.

60:2-(2-Carboxymethyl)-5-(2-chloro-4-trifluoromethylphenoxy)benzothiazole,mp 172-175.

61: 2-(2-Carbo-[2-(1-ethoxypropanoyl)oxy]phenyl)benzothiazole, mp 94-96.

62: 2-(2-Carboxy-5-chlorophenyl)-5-chlorobenzothiazole.

63: 2-(2-Carboxy-5-chlorophenyl)-6-phenylbenzothiazole.

64: 2-(2-Carboxy-5-chlorophenyl)-6-phenoxybenzothiazole.

65: 2-(2-Carboxy-5-chlorophenyl)-5-phenylbenzothiazole.

In the normal use of the aforesaid 2-(2-oxycarbonylcyclic)benzothiazoleplant growth and development modifiers, the active compounds usuallywill not be employed free from admixture or dilution, but ordinarilywill be used in a suitable formulated agricultural compositioncompatible with the method of application and comprising a plant growthand development modifying effective amount of at least one of saidactive compounds. Said benzothiazoles, like most pesticidal agents, maybe blended with the agriculturally acceptable surface-active agents andcarriers normally employed for facilitating the dispersion of activeingredients, recognizing the accepted fact that the formulation and modeof application of a plant growth and development modifier may affect theactivity of the material. The present active compounds may be applied,for example, as sprays, dusts, or granules to the area where plantgrowth and development modification is desired, the type of applicationvarying of course with the plant and the environment. Thus, thebenzothiazole compounds of this invention may be formulated as granulesof large particle size, as powdery dusts, as wettable powders, asemulsifiable concentrates, as solutions, and the like.

Granules may comprise porous or nonporous particles, such as attapulgiteclay or sand, for example, which serve as carriers for said activecompounds. The granule particles are relatively large, a diameter ofabout 400-2500 microns typically. The particles are either impregnatedwith the active compound from solution or coated with the compound,adhesive sometimes being employed. Granules generally contain 0.05-20%by weight, preferably 0.5-5%, active ingredient as the plant growth anddevelopment modifying effective amount. A typical granular formulationemployed for evaluation purposes contains 95% attapulgite clay (24/48mesh) and 5% 2-(2-carboxyphenyl)-5-phenylbenzothiazole.

Dusts are admixtures of said active compounds with finely divided solidssuch as talc, attapulgite clay, kieselguhr, pyrophyllite, chalk,diatomaceous earths, calcium phosphates, calcium and magnesiumcarbonates, sulfur, flours, and other organic and inorganic solids whichact as carriers for the plant growth and development modifier. Thesefinely divided solids have an average particle size of less than about50 microns. A typical dust formulation useful for modifying the growthand development of plants contains by weight 5 parts2-(2-carboxyphenyl)-5-phenylbenzothiazole and 95 parts talc.

The benzothiazole compounds of the present invention may be made intoliquid concentrates by dissolution or emulsification in suitable liquidsand into solid concentrates by admixture with talc, clays, and otherknown solid carriers used in the pesticide art. The concentrates arecompositions containing, as a plant growth and development modifyingeffective amount, about 5-50% the benzothiazole by weight and 95-50%inert material, which includes surface-active dispersing, emulsifying,and wetting agents, but even higher concentrations of active ingredientmay be employed experimentally. The concentrates are diluted with wateror other liquids for practical application as sprays, or with additionalsolid carrier for use as dusts. Typical carriers for solid concentrates(also called wettable powders) include fuller's earth, clays, silicas,and other highly absorbent, readily wetted inorganic diluents.

Manufacturing concentrates are useful for shipping low melting productsof this invention. Such concentrates are prepared by melting the solidproducts together with one percent or more of a solvent to produce aconcentrate which does not solidify on cooling to the freezing point ofthe pure product or below.

Useful liquid concentrates include the emulsifiable concentrates, whichare homogeneous liquid or paste compositions readily dispersed in wateror other liquid carriers. They may consist entirely of the activecompound with a liquid or solid emulsifying agent, or they may alsocontain a liquid carrier such as xylene, heavy aromatic naphthas,isophorone and other relatively non-volatile organic solvents. Forapplication, these concentrates are dispersed in water or other liquidcarriers and normally applied as sprays to areas to be treated.

Typical surface-active wetting, dispersing, and emulsifying agents usedin agricultural formulations include, for example, the alkyl andalkylaryl sulfonates and sulfates and their sodium salts; alkylamidesulfonates, including fatty methyl taurides; alkylaryl polyetheralcohols, sulfated higher alcohols; polyethylene oxides; sulfonatedanimal and vegetable oils; sulfonated petroleum oils; fatty acid estersof polyhydric alcohols and the ethylene oxide addition products of suchesters; and the addition products of long-chain mercaptans and ethyleneoxide. Many other types of useful surface-active agents are available incommerce. The surface-active agent, when used, normally comprises about1-15% by weight of the plant growth regulator composition.

Other useful formulations include simple solutions of the activeingredient in a solvent in which it is completely soluble at the desiredconcentration, such as acetone or other organic solvents.

A plant growth and development modifying effective amount of saidbenzothiazole in a plant growth and development modifying compositiondiluted for application is normally in the range of about 0.004% toabout 5% by weight. Many variations of spraying and dusting compositionsknown in the art may be used by substituting said plant growth anddevelopment modifying compounds of this invention into compositionsknown or apparent to the art. The plant growth and development modifyingcompositions of this invention may be formulated with other activeingredients, including insecticides, nematicides, acaricides,fungicides, other herbicides or plant growth regulators, fertilizers,etc.

In using the compositions to modify plant growth and developmentaccording to the method of this invention, it is only necessary that aplant growth and development modifying, or herbicidally, or plant growthregulant, effective amount of at least one of said benzothiazoles,depending on the objective, be applied to the locus where suchmodification, or control, or regulation is desired, generally a soillocus where agricultural crops are grown and either before or,preferably, after the plants have emerged. Liquid plant growth regulatorcompositions may be incorporated into the soil, applied to the soil as adrench, or sprayed on the foliage of growing plants. Solid compositionsmay be applied by broadcasting or in bands. For most applications, aplant growth and development modifying, or herbicidally, or plant growthregulant, effective amount will be about 0.005 to 8 kg, preferably 0.01to 2 kg, per hectare.

The plant growth and development modifiers of this invention wereinvestigated for activity in preemergence and postemergence testsaccording to the following procedure:

Flats were filled with a steam-sterilized sandy loam soil. Seeds of thefollowing test plant species were planted in furrows: cotton (Gossypiumhirsutum) or limabean (Phaseolus limensis), field corn (Zea mays L.),soybean (Glycine max), wheat (Triticum aestivum), barnyardgrass(Echinochload crus galli), johnsongrass (Sorghum halepense), pittedmorningglory (Ipomoea lacunosa), velvetleaf (Abutilon theophrasti),field bindweed (Convolvulus arvenia), and green foxtail (Setariaviridis). Soil was leveled to a 1 cm depth over the seeds.

In both the preemergence and postemergence tests the test chemicals wereapplied as aqueous acetone solutions at a rate equivalent to 8.0kilograms/hectare.

A flat for preemergence test was watered and the soil evenly drenchedwith the water-acetone solution of test chemical. The treated flat wasplaced in a greenhouse where it was watered regularly at the soilsurface for a period of 13 days. The effect of the test chemical wasthen recorded. In some tests individual plant species were examined forpercent kill and a vigor rating of one to five was assigned to thesurviving plants, a vigor of five signifying no chemical injury. Inother tests percent kill and vigor rating were combined in a singlerating called "percent control," which has the following significance:

    ______________________________________                                        Per-                                                                          cent                                                                          Con- Description of                                                                            Effect        Effect                                         trol Effect      on Crops      on Weeds                                       ______________________________________                                         0   No effect   No crop reduction                                                                           No weed control                                10               Slight discoloration                                                                        Very poor weed                                                  or stunting   control                                        20   Slight effect                                                                             Some discoloration,                                                                         Poor weed control                                               stunting or stand                                                             loss                                                         30               Crop injury more                                                                            Poor to deficient                                               pronounced but not                                                                          weed control                                                    lasting                                                      40               Moderate injury,                                                                            Deficient weed                                                  crop usually  control                                                         recovers                                                     50   Moderate    Crop injury more                                                                            Deficient to                                        effect      lasting, recovery                                                                           moderate weed                                                                 control                                        60               Lasting crop  Moderate weed                                                   injury no recovery                                                                          control                                        70               Heavy injury and                                                                            Control somewhat                                                stand loss    less than                                                                     satisfactory                                   80   Severe      Crop nearly   Satisfactory to                                     effect      destroyed a few                                                                             good weed control                                               survivors                                                    90               Only occasional                                                                             Very good to                                                    live plants left                                                                            excellent control                              100  Completely  Complete crop Complete weed                                       effective   destruction   destruction                                    ______________________________________                                    

Footnotes denoting other morphological responses observed were alsorecorded.

A flat for postemergence test was placed in a greenhouse for an 8 to 10day growing period. The test solution was then hand-sprayed onto thefoliage of the emerged test plants. After spraying, the foliage of thetest plants was kept dry for 24 hours after which time regular wateringwas resumed for a period of 13 days. The effect of the test chemical wasthen recorded in the same manner described for the preemergence tests.

The results of the preemergence and postemergence tests appear in TablesI and II, respectively. In the Tables, columns headed "PC," "V," "K,"and "F" refer to percent control, vigor, kill, and footnotes,respectively. Footnotes B, C, D, E, G, H, J, M, P, Q, and U, defined inthe Tables and described in more detail below, indicate plant growthregulator activity.

Stunting (footnote B) can retard the growth of grasses, which reducesmaintenance time for lawns, golf courses, and highway rights-of-way.Stunting in fruit trees may reduce stem growth, which can reduce pruningand trimming time. Stunting in cereal and broadleaf crops such as wheat,cotton, and soybeans may result in a shorter, thicker stalk whichresists lodging, in turn promoting higher yields.

Desiccation (footnote C) can reduce the pre-harvest moisture content incereals such as wheat, or in broadleaf crops such as sunflower.Desiccation can result in the loss of foliage, and in such plants assoybeans, cotton, peanuts, and potatoes the loss of foliage aids inharvesting.

Axillary growth stimulation (footnote D), or branching, can lead tomultiple stems in cereals such as wheat (tillering). An increase in thenumber of stems may increase the yield. In soybeans, axillarystimulation at flowering can result in more fruits, increasing yield.

Nastic response (footnote E) is manifested by twisting the bending ofthe plants and indicates a hormonal disruption. A natural and usefulnastic response is the curling of a tendril or stem around a support,e.g., in peas and pole beans.

Stimulation (footnote G) of vegetative growth in crops such as cloverresults in increased yields of forage. The stimulation of reproductivegrowth in fruits and cereals will also result in increased yields fromthose crops.

Defoliation (footnote H), or loss of plant foliage just prior toharvesting crops such as soybeans, cotton, peanuts and potatoes willfacilitate harvest of those crops. Foliage present at the time cotton isharvested may stain the cotton.

Intumescence (footnote J) indicates formation of abnormal swellings, adisruption of the hormonal balance that promotes normal growth.Intumescence-causing agents can promote the growth of tissue, such astobacco callus.

Negative root geotropism (footnote M) connotes the upward growth ofroots out of the soil and indicates disruption of the plant's normalhormonal balance. There can be a correlation between negative rootgeotropism and increase in the number of pods on soybean plants.

Deeper green lower leaves (footnote P) suggests delay of senescence,increased chlorophyll production, or chlorophyll retention. Thesephenomena mean greater photosynthesis, which may increase yield fromplants such as soybeans.

Leaf alteration (footnote Q) indicates disruption in the plant'shormonal balance. Leaves of plants can be altered to allow betterutilization of sunlight, which may enhance plant growth.

Benzothiazoles of this invention were also found in separate tests toinhibit the transport of auxin in excised stems of soybean plants, toaffect geotropic response in cress (Lepidium sativum) seedlings, and toenhance pod set in soybean plants.

    TABLE I      Preemergence Tests Plant       Cotton.sup.1    Barngr Bindweed Corn-F     Greenfox Mrnglory Johngr Lima Bean Soybean Velvetlf Wheat PC or PC or PC     or PC or PC or PC or PC or PC or PC or PC or Example V K F V K F V K F V K      F V K F V K F V K F V K F V K F V K F       1 2 90 BA 3 50 EB 0 100 0 2 50 EB  0 EB 2 85 B 0 100 B 2 50 BA 3 0 EB     2 85 B 2 4 0 B 5 0 0 4 30 0 5 0 0 5 0 0 5 0 0 4 40 BK 4 80 BK 5 0 0 4 0     BE 3 5 0 0 4 0 B 4 0 M 5 0 0       5 0 0 4 0 BM 4 60 B 5 0 0 4 3 0 BE 4     0 E 4 0 B 4 0 B 3 0 E 4 0 BE 4 0 BE 4 0 B 4 0 E 4 0 E 5 4 0 B 4 70 BE 5     0 0 4 0 B 4 60 BE 4 0 B 5 0 0 4 0 0 4 20 BE 5 0 0 7 4 0 MP 4 20 A 4 30     AI 4 0 M 4 10 E 5 0 0 2 0 BEIM 3 50 BM 3 70 B 4 0A 8 4 0 M 5 0 0 4 0 AM     4 0 M 5 0 0 5 0 0 4 0 AI 4 20 ABI 5 0 0 4 0 AM 9 5 0 0 4 0 B 5 0 0 5 0 0     5 0 0 5 0 0 5 0 0 3 0 B 4 0 B 4 0 B 10 10  AB1 20  AB1 30  AK 40  AB2E 0      0 10  AB1 20  ABI 50  B2E 0  0 10  AE 11 4 0 BE 5 0 0 5 0 0 4 0 B 4 0 A     5 0 0 0 100 K 4 30 B 5 0 0 4 0 BE 12 4 0 A 3 20 B 4 0 A 4 0 A 4 10 AB 3     90 B 4 0 A 3 50 B 0 100 0 4 0 A 13 5 0 0 5 0 0 5 0 0 5 0 0 4 0 AB 5 0 0     5 0 0 4 10 BM 4 10 A 5 0 0 14 5 0 0 5 0 0 0 100 0 5 0 0 4 50 AB 5 0 0 4     0 B 3 95 AM 4 35 AB 5 0 0 15 5 0 0 4 0 BE 5 0 0 5 0 0 4 0 BE 5 0 0 5 0 0     4 0 0 4 0 3 5 0 0 16 4 0 A 5 0 0 5 0 0 2 40 AB 4 30 B 4 0 B 4 0 B 4 0 B     4 50 B 4 0 A 17 5 0 0 5 0 0 5 0 0 5 0 0 5 0 0 5 0 0 5 0 0 5 0 0 5 0 0 5     0 0 18 4 0 B 3 80 0 4 30 0 4 70 0 3 50 B 4 0 B 4 0 BM 4 50 B 4 50 A 5 0     0 19 4 0 A 5 0 0 5 0 0 4 0 A 4 0 A 5 0 0 5 0 0 5 0 0 5 0 0 4 0 A 20 5 0     0 5 0 0 4 0 M 5 0 0 5 0 0 5 0 0 4 0 A 5 0 0 5 0 0 5 0 0 21 5 0 0 4 0 E 5     0 0 5 0 0 4 0 EK 5 0 0 5 0 0 4 30 K 4 0 E 5 0 0 22 5 0 0 5 0 0 5 0 0 5 0     0 5 0 0 3 40 B 5 0 0 5 0 0 5 0 0 5 0 0 23 4 0 A 4 40 0 4 0 A 5 0 0 4 0 A     5 0 0 4 0 A 4 0 A 4 0 A 4 0 A 24 5 0 0 4 0 C 5 0 0 5 0 0 4 0 A 5 0 0 5 0     0 5 0 0 4 10 AB 5 0 0 25 5 0 0 4 10 B 5 0 0 4 0 A 4 0 A 5 0 0 5 0 0 5 0     0 4 80 B 4 0 A 26 5 0 0 5 0 0 5 0 0 5 0 0 5 0 0 5 0 0 4 0 M 4 0 M 5 0 0     5 00 27 5 0 0 5 0 0 5 0 0 5 0 0 5 0 0 5 0 0 5 0 0 5 0 0 5 0 0 5 0 0 28 5     0 0 5 0 0 4 0 A 5 0 0 4 0 A 5 0 0 5 0 0 4 0 AI 5 0 0 4 0 A 29 4 0 ABE 4     0 BE 4 0 B 5 0 0 4 0 ABE 4 0 B 4 0 BE 4 20 BDI 4 0 BE 4 0 ABE 30 4 0 E 4     0 BE 4 0 BIM 5 0 0 4 20 BEM 5 0 0 4 0 B 3 0 BE 3 60 B 4 0 EM 31 5 0 0 5     0 0 5 0 0 5 0 0    5 0 0 4 0 B 4 0 BD 4 0 BE 4 0 B 32 5 0 0 5 0 0 5 0 0     5 0 0 5 0 0 4 0 B 4 60 K 4 20 B 5 0 0 5 0 0 33 5 0 0 5 0 0 5 0 0 5 0 0 5     0 0 5 0 0 5 0 0 5 0 0 5 0 0 5 0 0 34 5 0 0 5 0 0 5 0 0 4 0 B 5 0 0 5 0 0     5 0 0 5 0 0 5 0 0 5 0 0 35 4 0 ABE 3 70 BE 4 0 M 5 0 0 3 60 ABE 4 0 AB 3     40 BE 3 70 BE 4 50 BE 4 0 AE 36 3 0 BE 3 30 BE 3 30 BE 3 0 BE 3 30 BE 4     0 BE 3 80 BE 3 60 BE 3 40 BE 3 0 BE 37 5 0 0 5 0 0 5 0 0 5 0 0 5 0 0 5 0     0 5 0 0 4 0 B 5 0 0 5 0 0 38 5 0 0 5 0 0 5 0 0 5 0 0 5 0 0 5 0 0 5 0 0 4     0 M 5 0 0 5 0 0 39 5 0 0 4 0 B 5 0 0 4 30 A 5 0 0 5 0 0 5 0 0 5 0 0 5 0     0 5 0 0 40 4 0 M 4 0 B 4 0 M 4 0 M 4 0 M 4 0 M 4 0 M 4 0 BM 4 0 BM 4 0 M     41 4 0 ABMP 4 10 AB 3 0 ABM 4 0 BM 4 0 ABM 4 0 BM 3 40 ABIM 3 30 ABIM 4     0 AB 4 0 AM 42 4 0 AMP 5 0 0 4 0 AM 5 0 0 4 0 A 4 0 BM 4 0 AIM 4 0 BM 5     0 0 4 0 AM 43 5 0 0 5 0 0 5 0 0 5 0 0 4 0 AB 5 0 0 5 0 0 4 10 M 5 0 0 5     0 0 44 5 0 0 4 0 E 5 0 0 5 0 0 5 0 0 5 0 0 5 0 0 5 0 0 4 60 0 5 0 0 45 5     0 0 4 30 0 5 0 0 5 0 0 5 0 0 5 0 0 5 0 0 5 0 0 4 80 0 5 0 0 46 5 0 0 5 0     0 5 0 0 5 0 0 5 0 0 5 0 0 5 0 0 5 0 0 5 0 0 5 0 0 48 80  B4AEI 100  0 10      B1 100  0 90  B4AE 80  B5EA 50  B2AIE 20  B2E 100  0 10  B1E 49 10     AB1M 0  0 30  AB3 20  AB2 0  0 10  AB1M 30  AB1 50  B2 20  B1 0  0 50 60      AB3E 60  BE 80  B3E 60  B5E 40  BE 60  AB3E 40  B3 60  B3 30  BEI 40     AB1E 51 0  0 0  0 10  M 0  0 0  0 0  0 0  0.sup.1 10  M 0  0 40  E 54 0     M 0  0 30  B2M 0  0 0  M 0  M 0  M.sup.1 0  K 0  0 0  0 55 0  0 0  0 0     0 0  0 0  0 0  0 0  0 0  0 0  0 0  0 57 0  0 80  BE 30  B3MP 20  E 40     BE 10  M 60  B3M.sup.1 50  B3M 70  B 80  EB3 58 50  B3E 80  BE 50  B3PE     0  0 80  BE 40  B2E 80  B5E.sup.1 70  B5E 80  BE 50  EB2 59 0  0 20  B2A     40  B2M 20  B2AI 20  B2AI 20  B2 0  0.sup.1 0  0 40  B2AI 0  0 60 0  0 0      0 0  0 0  0 0  0 0  0 0  0.sup.1 0  0 0  0 0  0 61 0  0 10  AB1 20  AB1     0  M 10  AB1M 10  AB1M 10  AB3 10  B2 10  B1 0  0     FOOTNOTES     V = Vigor     5 = Plants normal     4 = Slight injury; plants will or have already recovered     3 = Moderate injury; plants expected to recover     2 = Moderate to severe injury; plants are not expected to recover     1 = Severe injury; plants will not recover     0 = Dead plant     K = % Kill     F = Footnote:     A = Necrosis     B = Stunted     C = Desiccation      D = Axillary Growth Stimulation     E = Nastic Responses     F = Necrotic Spots     G = Growth Stimulation     H = Defoliant     I = Chlorosis     J = Intumescence     K = Suspected germination failure     L = Stand may be affected by nonchemical factors     M = Negative root geotropism     N = Bleaching     P = Deeper green lower leaves     Q = Leaf alterations     U = Any other morphological response     Subfootnotes:     1 = 0%-4%     2 = 25%-49%     3 = 50%-74%     4 = 75%-100%     5 = refers to stunting only 75%-100% stunted with 0-30% phytotoicity     .sup.1 Data for cotton

    TABLE II      Postemergence Tests Plant       Cotton.sup.1    Barngr Bindweed Corn-F     Greenfox Mrnglory Johngr Lima Bean Soybean Velvetlf Wheat PC or PC or PC     or PC or PC or PC or PC or PC or PC or PC or Example V K F V K F V K F V K      F V K F V K F V K F V K F V K F V K F       1 4 0 BCM 4 0 BEM 4 0 M 4 0 BCM 4 0 BEM 4 0 M 3 0 EBM 3 0 EBCM 4 0 BEM 4      0 BM 2 5 0 0 5 0 0 5 0 0 4 0 A       4 0 A 4 0 AD 5 0 0 5 0 0 3 4 0 A 5     0 0 5 0 0 4 0 B 5 0 0 5 0 0 5 0 0 5 0 0 5 0 0 4 0 A 4 4 0 AB 3 95 B 5 0     0 4 70 0 4 0 0 4 0 B 3 0 ABE 4 0 AD 2 90 AB 5 0 0 5 5 0 0 4 0 BE 5 0 0 5     0 0 5 0 0 5 0 0 4 0 AB 4 0 AD 4 0 E 5 0 0 7 4 0 C 3 0 CE 4 0 C 3 0 BC 4     0 C 4 0 C 3 0 BDI 4 0 DI 3 0 CE 4 0 C 8 4 0 C 4 20 C 4 0 C 4 0 C 4 0 C 4     0 C 4 0 C 4 0 CD 4 0 C 4 0 C 9 5 0 0 5 0 0 5 0 0 5 0 0 5 0 0 5 0 0 5 0 0     4 0 A 5 0 0 5 0 0 10    0  0 30  MB2EC1 0  0 10  EC1 40  B2C1 10  H2 50     EB5PDM 10  EC1 0  0 11 4 0 C 5 0 0 5 0 0 5 0 0 5 0 0 5 0 0 4 0 C 4 0  5     0 0 5 0 0 12 5 0 0 3 70 BCM 5 0 0 4 0 M 3 0 BM 5 0 0 3 0 CD 4 0 CD 4 0     CM 5 0 0 13 5 0 0 5 0 0 5 0 0 5 0 0 5 0 0 5 0 0 4 0 C 4 0 C 5 0 0 5 0 0     14 5 0 0 5 0 0 5 0 0 4 20 0 5 0 0 5 0 0 4 0 C 5 0 0 5 0 0 5 0 0 15 5 0 0     4 90 BL 5 0 0 4 90 BC 4 0 BC 5 0 0 4 0 BCD 4 0 BCD 3 70 BC 5 0 0 16 5 0     0 3 0 C 5 0 0 5 0 0 5 0 0 5 0 0 4 0 CD 4 0 C 5 0 0 5 0 0 17 5 0 0 4 50 B     4 0 BC 5 0 0    5 0 0 4 0 C 4 0 BC 4 20 B 5 0 0 18 5 0 0 2 95 BC 5 0 0 4     30 C 4 0 BC 5 0 0 4 0 C 4 0 CD 4 0 B 5 0 0 19 5 0 0 5 0 0 5 0 0 5 0 0 5     0 0 5 0 0 4 0 A 5 0 0 5 0 0 5 0 0 20 5 0 0 5 0 0 5 0 0 5 0 0 5 0 0 5 0 0     4 0 A 4 0 A 5 0 0 5 0 0 21 5 0 0 0 100 L 5 0 0 4 90 C 3 70 BC 5 0 0 4 0     BC 3 0 BCD 4 0 BC 5 0 0 22 5 0 0 2 30 BC 5 0 0 4 0 C 5 0 0 5 0 0 4 0 C 5     0 0 5 0 0 5 0 0 23 5 0 0 5 0 0 5 0 0 5 0 0 5 0 0 5 0 0 4 0 CD 4 0 C 5 0     0 4 0 I 24 4 0 A 5 0 0 5 0 0 5 0 0 4 0 A 4 30 A 5 0 0 5 0 0 4 20 A 2 10     A 25 4 0 A 5 0 0 4 0 A 5 0 0 4 0 A 5 0 0 4 0 AD 4 0 A 5 0 0 4 0 A 26 4 0     C 4 30 C 4 0 BCM 5 0 0 4 0 BC 5 0 0 4 0 CIM 4 0 CDIM 5 0 0 4 0 CM 27 5 0     0 5 0 0 4 0 C 4 0 AI 5 0 0 5 0 0 4 0 CD 4 0 CD 5 0 0 5 0 0 28 5 0 0 5 0     0 5 0 0 3 20 A 5 0 0 4 0 I 4 0 AB 4 0 A 5 0 0 4 0 I 29 5 0 0 4 0 BE 5 0     0 5 0 0 5 0 0 5 0 0 3 0 ABD 4 0 ABDI 5 0 0 5 0 0 30 5 0 0 4 0 E 5 0 0 5     0 0 5 0 0 5 0 0 4 0 E 4 0 E 4 0 E 5 0 0 31 5 0 0 4 0 ABE 5 0 0 4 0 A 5 0     0 5 0 0 4 0 CB 4 0 BCD 4 0 0 5 0 0 32 4 0 C 4 0 C 4 0 BC 4 0 C 4 0 C 4 0     C 4 0 CB 4 0 BC 4 0 C 4 0 C 33 5 0 0 5 0 0 5 0 0 5 0 0 5 0 0 5 0 0 4 0 A     4 0 A 5 0 0 5 0 0 34 5 0 0 5 0 0 4 0 0 5 0 0 5 0 0 5 0 0 4 0 F 4 0 ABD 5     0 0 5 0 0 35 5 0 0 4 0 E 5 0 0 5 0 0 4 0 E 5 0 0 3 0 ABD 4 0 ABDI 4 0 E     5 0 0 36 4 0 0 4 0 E 5 0 0 4 50 L 4 0 E 4 0 0 4 0 BE 4 0 BDE 4 0 E 4 0 0     37 5 0 0 5 0 0 4 0 0 5 0 0 5 0 0 5 0 0 4 0 A 5 0 0 5 0 0 5 0 0 38 4 0 B     4 0 B 4 0 B 5 0 0 5 0 0 5 0 0 4 0 BD 4 0 BD 4 0 B 5 0 0 39 4 0 A 5 0 0 4     0 A 5 0 0 5 0 0 5 0 0 4 0 AD 4 0 D 5 0 0 4 0 A 40 5 0 0 4 0 B 4 0 0 5 0     0 4 0 0 5 0 0 4 0 BD 4 0 ABD 4 0 B 5 0 0 41 4 0 C 3 0 CE 4 0 C 4 0 C 4 0     C 4 0 C 3 0 BCDI 3 0 CDI 3 10 BCE 4 0 C 42 4 0 A 4 0 A 4 0 A 4 0 A 5 0 0     4 0 A 4 0 ADI 5 0 0 4 0 A 4 0 A 43 5 0 0 5 0 0 5 0 0 4 0 A 4 0 C 4 70 A     5 0 0 4 0 C 5 0 0 5 0 0 44 5 0 0 5 0 0 5 0 0 5 0 0 5 0 0 5 0 0 5 0 0 5 0     0 5 0 0 5 0 0 45 4 0 A 5 0 0 5 0 0 5 0 0 5 0 0 5 0 0 4 0 A 5 0 0 5 0 0 5     0 0 46 5 0 0 4 90 BL 4 0 C 4 30 CL 4 0 C 5 0 0 4 0 C 4 0 BC 4 20 BC 5 0     0 48    100  0 40  B1C 70  B1C 100  0 30  C 90  C4 70  B4C3H3D 90  BC 20      C 49    0  0 0  0 0  0 0  0 0  0 0  0 0  0 0  0 0  0 50 80  A 20  B1E     10  AM    30  B2EA 40  AB1 70  B2EAHE 60  B4AIEMP 20  B1E 0  0 51 20     AB1 10  A 20  AB1 0  0 0  0 10  A 10  A.sup.1 10 A 0  0 10  A 54 10  A 0      0 0  M 0  0 10  A 10  B1 10  A.sup.1 10  A 0  0 10  AI 55 10  A 10  A     10  A 0  0 0  0 10  A 10  A.sup.1 10  AE 10  A 0  0 57 20  AB2EM 80  AB3     30  AB2EM 10  A 20  AB4E 20  AM 40  AB2E.sup.1 40  AB3DE 20  AB3E 10  A     58 60  AB1 20  B3E 20  AB1EM 0  0 10  B3E 40  AB2EM 30  AB2EM.sup.1 20     AB3DEIM 10  B3E 10  A 59 0  0 0  0 10  AM 10  A 40  AB1 40  AB1 20  AB1     20  AB1 30  AEI 0  0 60 40  B1C2 50  B2C2 10 B1C1E 0  0 100  C 60  B1C3     50  B2H3.sup.1 40  B1C2DI 60  B1C3I 10  A 61 0  0 0  0 0  0 0  0 0  0 0     0 0  0.sup.1 0  0 0  0 0  0     FOOTNOTES     The footnotes in Table I are also applicable in Table II.

What is claimed is:
 1. Plant growth and development modifying2-(2-oxycarbonylcyclic)benzothiazoles of the formula ##STR5## wherein Uis selected from -hydrogen, -halogen, -lower alkyl, -lower haloalkyl,-lower alkoxy, -phenyl, and -phenoxy optionally carrying -halogen and-lower haloalkyl substituents;V is selected from -hydrogen and -halogen,or U and V taken together are --C₄ H₄ -- joining adjacent ringpositions; Y is selected from -hydrogen and -lower alkoxy; Z is selectedfrom(a) -phenyl, provided U, V and Y are not each -hydrogen; or (b)-phenyl carrying 1 or 2 substituents independently selected from-halogen or two substituents taken together are --C₄ H₄ -- joiningadjacent ring positions; or (c) a six-membered saturated or partiallyunsaturated carbocycle, optionally carrying a bicyclic --CH₂ --bridge,and provided U is -hydrogen, -halogen or -phenyl and V and Y are-hydrogen; or (d) a five or six-membered aromatic heterocycle containing2 nitrogen atoms as the only hetero atoms, provided U is -hydrogen,-halogen or -phenyl and V and Y are -hydrogen; or (e) a pyridine ring,provided U is -halogen or -phenyl and V and Y are -hydrogen; and Z alsocarries a 2-oxycarbonyl substituent of the formula

    --COOW

in which W is selected from -hydrogen, -lower alkyl, and anagriculturally acceptable cation.
 2. Compounds of claim 1 wherein W is-hydrogen or an agriculturally acceptable cation.
 3. Compounds of claim1 wherein U is a 5- or 6-substituent selected from -halogen, -lowerhaloalkyl, -phenyl, and -phenoxy optionally carrying -halogen and -lowerhaloalkyl substituents.
 4. Compounds of claim 1 wherein V and Y are-hydrogen.
 5. Compounds of claim 1 wherein Z is selected from -phenyl ora pyridine ring.
 6. A compound of claim 1 selected from2-(2-carboxyphenyl)-5-phenylbenzothiazole,2-(2-carboxyphenyl)-6-(2-chloro-4-trifluoromethylphenoxy)benzothiazole,2-(2-carboxyphenyl)-5-(2-chloro-4-trifluoromethylphenoxy)benzothiazole,2-(2-carboxyphenyl)-5-trifluoromethylbenzothiazole,2-(2-carboxyphenyl)-6-phenylbenzothiazole, agriculturally acceptablecation salts of 2-(2-carboxyphenyl)-5-trifluoromethylbenzothiazole,2-(2-carboxyphenyl)-6-phenoxybenzothiazole,2-(2-carboxy-4-chlorophenyl)-6-phenylbenzothiazole,2-(2-carboxy-5-chlorophenyl)-6-phenylbenzothiazole,2-(2-carboxy-4-chlorophenyl)-6-phenoxybenzothiazole,2-(2-carboxy-5-chlorophenyl)-6-phenoxybenzothiazole,2-(2-carboxyphenyl)-5-phenoxybenzothiazole, and2-(2-carboxy-6-pyridinyl)-5-phenylbenzothiazole. 7.2-(2-Carboxyphenyl)-6-(2-chloro-4-trifluoromethylphenoxy)benzothiazole.8. 2-(2-Carboxyphenyl)-5-phenylbenzothiazole. 9.2-(2-Carboxyphenyl)-5-phenoxybenzothiazole. 10.2-(2-Carboxy-6-pyridinyl)-5-phenylbenzothiazole.
 11. Plant growth anddevelopment modifying compositions comprising in admixture with anagriculturally acceptable carrier a plant growth and developmentmodifying effective amount of at least one2-(2-oxycarbonylcyclic)benzothiazole of the formula ##STR6## wherein Uis selected from -hydrogen, -halogen, -lower alkyl, -lower haloalkyl,-lower alkoxy, -phenyl, and -phenoxy optionally carrying -halogen and-lower haloalkyl substituents;V is selected from -hydrogen and -halogen,or U and V taken together are --C₄ H₄ --joining adjacent ring positions;Y is selected from -hydrogen and -lower alkoxy; Z is selected from(a)-phenyl optionally carrying 1 or 2 substituents independently selectedfrom -halogen, -nitro, or two substituents taken together are --C₄ H₄--joining adjacent ring positions; or (b) a six-membered saturated orpartially unsaturated carbocycle, optionally carrying a bicyclic --CH₂--bridge, and provided U is -hydrogen, -halogen or -phenyl and V and Yare -hydrogen; or (c) a five or six-membered aromatic heterocyclecontaining 1 or 2 nitrogen atoms, as the only hetero atoms, provided Uis -hydrogen, -halogen or -phenyl and V and Y are -hydrogen; and Z alsocarries a 2-oxycarbonyl substituent of the formula

    --COOW

in which W is selected from -hydrogen, -lower alkyl, and anagriculturally acceptable cation.
 12. Compositions of claim 11 whereinsaid 2-(2-oxycarbonylcyclic)benzothiazole is selected from2-(2-carboxyphenyl)-5-phenylbenzothiazole,2-(2-carboxy-3-nitrophenyl)-5-chlorobenzothiazole,2-(2-carboxyphenyl)-6-(2-chloro-4-trifluoromethylphenoxy)benzothiazole,2-(2-carboxyphenyl)-5-(2-chloro-4-trifluoromethylphenoxy)benzothiazole,2-(2-carboxyphenyl)-5-trifluoromethylbenzothiazole,2-(2-carboxyphenyl)-6-phenylbenzothiazole, agriculturally acceptablecation salts of 2-(2-carboxyphenyl)-5-trifluoromethylbenzothiazole,2-(2-carboxyphenyl)-6-phenoxybenzothiazole,2-(2-carboxy-4-chlorophenyl)-6-phenylbenzothiazole,2-(2-carboxy-5-chlorophenyl)-6-phenylbenzothiazole,2-(2-carboxy-4-chlorophenyl)-6-phenoxybenzothiazole,2-(2-carboxy-5-chlorophenyl)-6-phenoxybenzothiazole,2-(2-carboxyphenyl)-5-phenoxybenzothiazole, and2-(2-carboxy-6-pyridinyl)-5-phenylbenzothiazole.
 13. Compositions ofclaim 11 wherein said 2-(2-oxycarbonylcyclic)benzothiazole is2-(2-carboxyphenyl)-6-(2-chloro-4-trifluoromethylphenoxy)benzothiazole.14. Compositions of claim 11 wherein said2-(2-oxycarbonylcyclic)benzothiazole is2-(2-carboxyphenyl)-5-phenylbenzothiazole.
 15. Compositions of claim 11wherein said 2-(2-oxycarbonylcyclic)benzothiazole is2-(2-carboxyphenyl)-5-phenoxybenzothiazole.
 16. Compositions of claim 11wherein said 2-(2-oxycarbonylcyclic)benzothiazole is2-(2-carboxy-6-pyridinyl)-5-phenylbenzothiazole.
 17. A method ofmodifying the growth and development of plants which comprises applyingto the locus where such modification is desired a plant growth anddevelopment modifying effective amount of at least one2-(2-oxycarbonylcyclic)benzothiazole of the formula ##STR7## wherein Uis selected from -hydrogen, -halogen, -lower alkyl, -lower haloalkyl,-lower alkoxy, -phenyl, and -phenoxy optionally carrying -halogen and-lower haloalkyl substituents;V is selected from -hydrogen and -halogen,or U and V taken together are --C₄ H₄ --joining adjacent ring positions;Y is selected from -hydrogen and -lower alkoxy; Z is selected from (a)-phenyl optionally carrying 1 or 2 substituents independently selectedfrom -halogen, -nitro, or two substituents taken together are --C₄ H₄--joining adjacent ring positions; or(b) a six-membered saturated orpartially unsaturated carbocycle, optionally carrying a bicyclic --CH₂--bridge, and provided U is -hydrogen, -halogen or -phenyl and V and Yare -hydrogen; or (c) a five or six-membered aromatic heterocyclecontaining 1 or 2 nitrogen atoms, as the only hetero atoms, provided Uis -hydrogen, -halogen or -phenyl and V and Y are -hydrogen; and Z alsocarries a 2-oxycarbonyl substituent of the formula

    COOW

in which W is selected from -hydrogen, -lower alkyl, and anagriculturally acceptable cation.
 18. A method according to claim 17wherein said 2-(2-oxycarbonylcyclic)benzothiazole is selected from one2-(2-carboxyphenyl)-5-phenylbenzothiazole,2-(2-carboxy-3-nitrophenyl)-5-chlorobenzothiazole,2-(2-carboxyphenyl)-6-(2-chloro-4-trifluoromethylphenoxy)benzothiazole,2-(2-carboxyphenyl)-5-(2-chloro-4-trifluoromethylphenoxy)benzothiazole,2-(2-carboxyphenyl)-5-trifluoromethylbenzothiazole,2-(2-carboxyphenyl)-6-phenylbenzothiazole, agriculturally acceptablecation salts of2-(2-carboxyphenyl)-5-trifluoromethylbenzothiazole,2-(2-carboxyphenyl)-6-phenoxybenzothiazole,2-(2-carboxy-4-chlorophenyl)-6-phenylbenzothiazole,2-(2-carboxy-5-chlorophenyl)-6-phenylbenzothiazole,2-(2-carboxy-4-chlorophenyl)-6-phenoxybenzothiazole,2-(2-carboxy-5-chlorophenyl)-6-phenoxybenzothiazole,2-(2-carboxyphenyl)-5-phenoxybenzothiazole, and2-(2-carboxy-6-pyridinyl)-5-phenylbenzothiazole.
 19. A method accordingto claim 17 wherein said 2-(2-oxycarbonylcyclic)benzothiazole is2-(2-carboxyphenyl)-6-(2-chloro-4-trifluoromethylphenoxy)benzothiazole.20. A method according to claim 17 wherein said2-(2-oxycarbonylcyclic)benzothiazole is2-(2-carboxyphenyl)-5-phenylbenzothiazole.
 21. A method according toclaim 17 wherein said 2-(2-oxycarbonylcyclic)benzothiazole is2-(2-carboxyphenyl)-5-phenoxybenzothiazole.
 22. A method according toclaim 17 wherein said 2-(2-oxycarbonylcyclic)benzothiazole is2-(2-carboxy-6-pyridinyl)-5-phenylbenzothiazole.
 23. A method ofcontrolling the growth of plants which comprises applying to the locuswhere control is desired a herbicidally effective amount of at least one2-(2-oxycarbonylcyclic)benzothiazole selected from2-(2-carboxyphenyl)-5-phenylbenzothiazole,2-(2-carboxy-3-nitrophenyl)-5-chlorobenzothiazole,2-(2-carboxyphenyl)-6-(2-chloro-4-trifluoromethylphenoxy)benzothiazole,and2-(2-carboxyphenyl)-5-(2-chloro-4-trifluoromethylphenoxy)benzothiazole24. A method according to claim 23 wherein said2-(2-oxycarbonylcyclic)benzothiazole is2-(2-carboxyphenyl)-6-(2-chloro-4-trifluoromethylphenoxy)benzothiazole.25. A method of regulating the growth of plants which comprises applyingto the locus where regulation is desired a plant growth regulanteffective amount of at least one 2-(2-oxycarbonylcyclic)benzothiazoleselected from 2-(2-carboxyphenyl)-5-phenylbenzothiazole,2-(2-carboxyphenyl)-5-trifluoromethylbenzothiazole,2-(2-carboxyphenyl)-6-phenylbenzothiazole, agriculturally acceptablecation salts of 2-(2-carboxyphenyl)-5-trifluoromethylbenzothiazole,2-(2-carboxyphenyl)-6-(2-chloro-4-trifluoromethylphenoxy)benzothiazole,2-(2-carboxyphenyl)-6-phenoxybenzothiazole,2-(2-carboxy-4-chlorophenyl)-6-phenylbenzothiazole,2-(2-carboxy-5-chlorophenyl)-6-phenylbenzothiazole,2-(2-carboxy-4-chlorophenyl)-6-phenoxybenzothiazole,2-(2-carboxy-5-chlorophenyl)-6-phenoxybenzothiazole,2-(2-carboxyphenyl)-5-phenoxybenzothiazole,2-(2-carboxy-6-pyridinyl)-5-phenylbenzothiazole, and2-(2-carboxyphenyl)-5-(2-chloro-4-trifluoromethylphenoxy)benzothiazole.26. A method according to claim 25 wherein said2-(2-oxycarbonylcyclic)benzothiazole is selected from2-(2-carboxyphenyl)-5-phenylbenzothiazole,2-(2-carboxyphenyl)-5-phenoxybenzothiazole, and2-(2-carboxy-6-pyridinyl)-5-phenylbenzothiazole.
 27. A method accordingto claim 26 wherein said 2-(2-oxycarbonylcyclic)benzothiazole is2-(2-carboxyphenyl)-5-phenylbenzothiazole.